PURPOSE: To accurately perform the display of a flow amount and to reduce current consumption, by a method wherein a magnetic sensing element senses magnets passing the opposed position to output detection signals corresponding to the number of the sensed magnets and the flow amount of gas is detected on the basis of the detection signals.
CONSTITUTION: A magnetic resistance element 44 is arranged to a counter part 25 at the position successively opposed to magnets 39,... by the rotary motion of a magnet disc 38 so as to interpose an upper case 20. When a rotary member 38 rotates corresponding to a gas passing flow amount, the magnetic resistance element 44 senses the magnets 39,... passing the opposed position and changes in resistance upon the reception of the magnetical action of each magnet to output a pulse signal on the basis of the change in resistance. This pulse signal is sent to an electronic counter 45 and the flow amount of gas is displayed on the liquid crystal plate 46 mounted to the electronic counter 45.
KASHIWAKURA TOSHIYUKI
MIZUTA TOSHIAKI
IWATA SEIICHI
RICOH KK
RICOH SEIKI CO LTD